This game is a fantastic example of experimental gaming in a easy to pick up form. I have not played the steam version but based on my experience with the old version, I could not recommend this game more highly for gamers looking for something different. Without spoilers, if you liked Braid, you'll like this a lot.

The game isn't very long but it is well worth the price and every second of gameplay. Also consider VVVVVV, another incredible retro-style experimental game.

And what exactly is "experimental" here? It's just a really generic platformer. The "eversion" itself really does nothing gameplay-wise and is there just for cosmetics. There is couple of places where everting is required for 100%-completion, but they are really linear, no-brainer.

PS. I'm not saying this a bad game, no. The game is OK and the art is good. I just don't see why this game should've come into existence since I can't really see what it has to add to gaming experience =)

You're absolutely right, there isn't much experimenting going on in the gameplay, and the gameplay isn't that great either but I don't think there is supposed to be. I think its experimental from a narrative and artistic standpoint, it toys with expectations and perception. Eversion, among other experimental games like the wild ones that Cactus Squid makes or the ones found over here: http://indiegames.com/best-of-features/index.php?c=ex&y=2009&gid=0 sometimes experiment with gameplay, sometimes with narrative, and sometimes the overall presentation or message.

In the sense that a game like Portal experiments with gameplay, Eversion and many of these other games do not, but they do experiment with the same kind of elements as experimental films but with the benifits of their interactive medium. I think it's just a different kind of appeal, I think eversion falls into this category and is more about toying with the ordirnary and expected than with being a great platformer.